The invention is generally related to subsea abandonment and recovery operations and more particularly to the hooks used in such operations.
A conventional hook designed for subsea operations usually involves a padeye on the tip end which serves as a rigging aid to offshore personnel during subsea operations. The padeye provides for attachment of a trip line to move the tip end of the hook into a desired orientation and position for releasing or catching an item.
While there are a number of hooks for subsea operations that have been specifically designed and built to have a padeye at the tip end to make them usable in operations that require a specific movement of the tip, there are also many hooks in use in the offshore industry that have not been designed and built with an integral padeye at the tip end. The result is that the use of these hooks can be very limited, especially in recovery operations. Because hooks used in subsea operations must meet specific industry standard requirements regarding lifting capacity, tensile strength, etc., modification of existing hooks by means such as drilling holes therethrough or welding an accessory padeye to the hook will void the certification of the existing hook. The hooks used in subsea operations are used to lower and recover very large diameter wire rope and chains where the chain material may be several inches in diameter and a single chain link may be a few feet long. Thus, the hooks are large, heavy, and expensive pieces of equipment that must have a large lifting capacity.